TWI410657B - Method and system for maintaining a gnss receiver in a hot-start state - Google Patents

Abstract

Aspects of a method and system for maintaining a GNSS receiver in a hot-start state are provided. A GNSS receiver in a standby mode may transition from a sleep state to a wakeup state to acquire ephemeris from, for example, GPS signals, GALILEO signals, and/or GLONASS signals. The acquired ephemeris may be stored and utilized for the GNSS receiver to generate a navigation solution in a normal mode. The GNSS receiver may transition from the normal mode to the sleep state or the wakeup state in standby mode. A sleep period and a wakeup period for the full sleep-wakeup cycle in the standby mode may be predetermined or dynamically adjusted based on required QoS, quality of satellite signals, and/or user inputs. The sleep period and the wakeup period may be selected in a way to ensure a valid and complete ephemeris to be acquired.

Description

Satellite communication method and system

The present invention relates to signal processing for communication systems and, more particularly, to a method and system for maintaining a GNSS receiver in a hot-start state.

A Global Navigation System (GNSS) such as the Global Positioning System (GPS) includes a combination of 24 earth-orbiting satellites. Each GPS satellite orbits a precise orbit of 11,000 miles above Earth. The GPS receiver locks at least three satellites to determine their location. Each satellite transmits a signal modulated with a unique pseudo-noise (PN) code at the same frequency. The signal received by the GPS receiver is a mixture of signals transmitted by all satellites visible to the receiver. The GPS receiver detects the transmission of a particular satellite based on the corresponding PN code. For example, the received signal is associated with a shifted form of the satellite's PN code to identify the source satellite of the received signal and to achieve synchronization with subsequent transmissions of the identified satellite.

When the GPS receiver is powered up, it undergoes a series of states to initially determine a navigation solution that includes location, rate, and time. Subsequently, the satellite signals are continuously tracked and the position is calculated periodically. The precise orbital information (often referred to as ephemeris or ephemeris data) transmitted by each satellite is used to calculate the navigation scheme. Once the GPS signal is acquired, the ephemeris or ephemeris data for a particular satellite is decoded from the orbital data. Each satellite broadcasts its own ephemeris data, which lasts for 18 seconds and repeats every 30 seconds.

Other disadvantages and disadvantages of the prior art will be apparent to those skilled in the art from a comparison of the present invention, which will be described in conjunction with the drawings.

The present invention proposes a method and system for maintaining a GNSS receiver in a hot-start state. The invention will be fully illustrated and/or described in conjunction with the appended claims,

According to an aspect of the present invention, the present invention provides a satellite communication method, including:

When the navigation satellite system receiver is in a sleep state in a standby mode, transitioning from the sleep state to the awake state in a standby mode to obtain the latest ephemeris;

The navigation information is determined using the acquired latest ephemeris when the navigation satellite system receiver subsequently transitions from the standby mode to the normal mode of operation.

Advantageously, the method further comprises, after acquiring the latest ephemeris, transitioning from the awake state back to the sleep state in the standby mode.

Advantageously, said latest ephemeris is obtained from a GPS signal, a GLONASS signal and/or a Galileo signal.

Advantageously, the method further comprises storing said acquired latest ephemeris in said navigation satellite system receiver.

Advantageously, the method further comprises returning from said normal mode of operation to said sleep state in said standby mode.

Advantageously, the method further comprises returning from said normal mode of operation to said awake state in said standby mode.

Advantageously, the method further comprises maintaining said normal mode of operation after transitioning from said standby mode to said normal mode of operation.

Advantageously, for the standby mode, the sleep period of the sleep state and the wake-up period of the wake state are preset or dynamically adjusted.

Advantageously, the sleep period of the sleep state and the wake-up period of the wake state are determined based on QoS (Quality of Service), quality of the acquired latest ephemeris, and/or user input.

Advantageously, the sleep period of the sleep state is less than the period in which the latest ephemeris is changed by one or more satellites.

Advantageously, the wake-up period of the awake state is greater than or equal to the period required to collect the latest ephemeris.

According to still another aspect of the present invention, the present invention provides a satellite communication system comprising:

One or more circuits for a navigation satellite system receiver, wherein the one or more circuits are used to place the sleep state in a standby mode when the navigation satellite system receiver is in a standby state in a standby mode Switch to wake state to get the latest ephemeris; and

The one or more circuits are operative to determine navigation information using the acquired ephemeris when the navigation satellite system receiver subsequently transitions from the standby mode to the normal mode of operation.

Advantageously, said one or more circuits are operative to transition said awake state back to said sleep state in said standby mode after said latest ephemeris is acquired.

Advantageously, said latest ephemeris is obtained from a GPS signal, a GLONASS signal and/or a Galileo signal.

Advantageously, said one or more circuits are operable to store said acquired latest ephemeris in said navigation satellite system receiver.

Advantageously, said one or more circuits are operable to return said normal mode of operation to said sleep state in said standby mode.

Advantageously, said one or more circuits are operable to return said normal mode of operation to said awake state in said standby mode.

Advantageously, said one or more circuits are operative to maintain said normal mode of operation after transitioning from said standby mode to said normal mode of operation.

Advantageously, for the standby mode, the sleep period of the sleep state and the wake-up period of the wake state are preset or dynamically adjusted.

Advantageously, the dormant period of the sleep state and the wake-up period of the awake state are determined based on QoS (Quality of Service, quality of the acquired ephemeris and/or user input).

Advantageously, the sleep period of the sleep state is less than the period in which the latest ephemeris is changed by one or more satellites.

Advantageously, the wake-up period of the awake state is greater than or equal to the period required to collect the latest ephemeris.

The detailed description of the specific embodiments of the invention, in the claims

The present invention relates to a method and system for maintaining a GNSS receiver in a hot-start state. Aspects of the invention enable GNSS enabled handsets to operate in both normal mode and standby mode. In standby mode, the GNSS enabled handset is periodically or aperiodically configured to switch between a sleep state and an awake state in the standby mode. For example, in standby mode, the GNSS enabled handset is configured to switch from a sleep state in standby mode to an awake state in standby mode. In the wake-up state in standby mode, the GNSS-enabled handset can turn on the corresponding GNSS front-end to track satellite signals and obtain the latest navigation information (such as the latest ephemeris from satellite signals). The acquired latest ephemeris can be stored and used to launch a GNSS-enabled handset in normal mode in the future to generate navigation information. Satellite signals include GPS signals, GALILEO signals, and/or GLONASS (Global Navigation Satellite System) signals. Handheld machines that support GNSS can operate in different ways. For example, after the different operations of the normal mode are initiated, the GNSS enabled handset is configured to transition from the normal mode to the sleep state or the awake state, or to remain in the normal mode. The sleep cycle of the sleep state and the wake-up cycle of the wake state are preset or dynamically adjusted. The sleep period and the wake-up period are determined based on QoS (Quality of Service, quality of satellite signals, and/or user input.) In order to generate a navigation scheme for the GNSS-enabled handset, the GNSS-enabled handset is in standby mode. After the sleep state transitions to the wake-up state of the standby mode, the latest ephemeris can be acquired and used. In short, the selected sleep period is less than the period in which the latest ephemeris is changed by one or more satellites. The selected wake-up period should be long enough. To collect the latest ephemeris.

1 is a schematic diagram of an exemplary GNSS satellite navigation system that maintains a GNSS receiver in a warm-start state, in accordance with an embodiment of the present invention. Referring to Fig. 1, a GNSS satellite navigation system 100 is illustrated, including a GNSS enabled handset 110 (which may be a GNSS enabled cellular phone 110a, a GNSS enabled smartphone 110b, a GNSS enabled laptop 110c), A plurality of GNSS satellites 120a-120c and a wireless communication network 130.

The GNSS enabled handset 110 includes appropriate logic and/or code for receiving satellite broadcast signals from the GNSS satellites 120a-120c to determine the exact location of the GNSS enabled handset 110. The GNSS enabled handset 110 is capable of transmitting and receiving radio signals over a wireless communication network 130 that follows, for example, 3GPP (3rd Generation Partnership Project), 3GPP2 (3rd Generation Partnership Project 2) , 3rd Generation Partnership Project 2), WiFi (Wireless Fidelity,) and/or WiMAX (ie, Worldwide Interoperability for Microwave Access) communication standard. The GNSS enabled handset 110 supports various modes of operation (such as normal mode (high power), standby mode (low power)) to accomplish different tasks in acquiring and maintaining GNSS information.

The normal mode includes a mode in which the GNSS enabled handset 110 is capable of operating at its normal current consumption level to support its primary system CPU to function properly with all major functions. In the normal mode, the GNSS enabled handset 110 uses a high speed clock that consumes more power than the low speed clock used in the standby mode.

The standby mode includes a mode in which the GNSS enabled handset 110 operates at its low current consumption level. For example, in standby mode, GNSS enabled handset 110 operates at a low power level to monitor and initiate bus activity. In standby mode, the GNSS enabled handset 110 is configured to shut down depending on the primary function of the primary system CPU. In this regard, the GNSS enabled handset 110 in standby mode uses a low frequency clock instead of the high frequency clock used in the normal mode.

In the standby mode, the GNSS enabled handset 110 turns off the corresponding radio component that transmits and/or receives data over the wireless communication network 130. However, the GNSS enabled handset 110 is configured to turn on or off components associated with receiving GNSS material when needed. The GNSS enabled handset 110 in standby mode can be in an awake state or a sleep state. The awake state in the standby mode corresponds to the case where the GNSS enabled handset 110 is in standby mode and is capable of receiving GNSS data. The sleep state in the standby mode corresponds to the case where the GNSS-enabled handset 110 is in standby mode and is not capable of receiving GNSS data.

Depending on the GNSS information, such as the most recent GNSS location, current GNSS time, and/or ephemeris data, the GNSS enabled handset 110 may apply different policies (eg, cold-start, when the GNSS initiates acquisition of GNSS information, Warm-start, hot-start. In this regard, in standby mode, the GNSS enabled handset 110 can be configured to maintain GNSS information in a warm boot state by periodically waking up and running for as long as possible to decode the latest ephemeris. The decoded ephemeris is used for subsequent launches to improve the time (TTFF, time to first fix) of the GNSS enabled handset 110.

The GNSS satellites 120a-120c include suitable logic, circuitry, and/or code for generating and broadcasting appropriate radio-frequency (RF) signals. The broadcast RF signal includes various navigational information such as orbital information (often referred to as ephemeris or ephemeris data). The orbital information includes the orbital position as a function of GNSS time. The broadcast ephemeris of the GNSS satellites 120a-120c changes every 2 hours and is valid for a certain period of time in the future, for example 4 hours. The broadcast ephemeris is received and decoded by a GNSS satellite receiver that can be integrated into the GNSS enabled handset 110. The broadcast ephemeris is used to determine a navigation scheme, such as the location, rate, and clock information of the handset 110 that supports the GNSS.

Wireless communication network 130 includes suitable logic, circuitry, and/or code for providing various voice and/or data over CDMA2000, WCDMA, GSM, UMTS (Universal Mobile Telecommunications System), WiFi, or WiMAX communication standards. service.

In operation, the GNSS enabled handset 110 can receive satellite broadcast signals from the GNSS satellites 120a-120c to determine a navigation scheme, such as a positioning coordinate of the GNSS enabled handset 110. A series of states can be performed to acquire and maintain GNSS navigation information (such as ephemeris) to calculate a navigation scheme for the GNSS enabled handset 110. For example, in the standby state, the GNSS-enabled handset 110 maintains the ephemeris in a warm-start state by periodically waking up to acquire GNSS broadcast signals from the GNSS satellites 120a-120c and running as long as possible to decode the ephemeris. The latest ephemeris is used at the subsequent startup to improve the time to first location (TTFF) of the GNSS enabled handset 110. The determined navigation scheme can be applied to various location based services through the GNSS enabled handset 110 and/or the wireless communication network 130.

2 is a state diagram of an exemplary GNSS receiver operation to maintain a GNSS receiver in a warm start state, in accordance with an embodiment of the present invention. Referring to FIG. 2, an exemplary operational state machine is illustrated, including a normal mode 210, a standby mode 220. The standby mode 220 includes a sleep state 222 and an awake state 224.

In normal mode 210, GNSS enabled handset 110 is fully powered to perform GNSS signal search, acquisition, metrology, and satellite tracking functions. The full operating cycle of normal mode 210 is software tunable. The GNSS enabled handset 110 in the normal mode 210 outputs location information at a user defined rate. Depending on the implementation, the GNSS enabled handset 110 is automatically switched between the standby mode 220 and the normal mode 210 to conserve power, or to remain in the normal mode after switching from the standby mode. In the standby mode 220, the GNSS enabled handset 110 operates at minimum power that is significantly less than the power in the normal mode 210. In this regard, in the standby mode 220, the GNSS enabled handset 110 can be configured in the sleep state 222 or the awake state 224. In sleep state 222, GNSS enabled handset 110 is configured to turn off GNSS RF components to save power.

The GNSS enabled handset 110 can be configured to periodically wake up from the sleep state 222 and enter the awake state 224 to enable the latest ephemeris to be acquired with low power consumption. The ephemeris of a satellite such as GNSS satellites 120a-120c changes every 2 hours, preferably every 4 hours. A suitable wake-up interval of, for example, every 2 hours can be used. In the awake state 224, the GNSS enabled handset 110 can acquire ephemeris and primary GNSS navigation information without having to fully boot. For example, the GNSS enabled handset 110 can wake up without even having to open a user interface component such as a display screen. In the awake state 224, the GNSS enabled handset 110 remains long enough to acquire a complete ephemeris. The GNSS enabled handset 110 consumes less power for various operations during the awake state 224. The GNSS enabled handset 110 stores the acquired ephemeris data to provide the latest ephemeris for the activation of the GNSS, thereby enabling, for example, to calculate a navigation scheme or perform a navigation update in the normal mode 210. The GNSS enabled handset 110 may return to the sleep state 222 or the awake state 224 of the standby mode 220 after the navigation update. Depending on the implementation, the GNSS enabled handset 110 remains in the normal mode after the navigation update. The sleep-wake full loop of the standby mode 220 can be software adjusted by different time controls. For example, the GNSS enabled handset 110 is configured to update the navigation information of the GNSS enabled handset 110 by setting a wakeup timer and/or a sleep timer. The wake-up timer and/or sleep timer are preset and/or dependent on, for example, the required QoS and/or required ephemeris data quality.

3 is a schematic diagram of a preferred apparatus for supporting GNSS, the apparatus including a GNSS receiver for maintaining a hot start state, in accordance with an embodiment of the present invention. Referring to FIG. 3, a GNSS enabled handset 110 is illustrated that includes an antenna 302, a GNSS front end 304a, a communication front end 304b, a processor 306, a memory 308, and a user interface 310.

Antenna 302 includes suitable logic, circuitry, and/or code for receiving L-band signals from a plurality of GNSS satellites 120a-120c. The antenna 302 is capable of transmitting and/or receiving radio signals by, for example, a 3G radio communication system for 3G inter-device communication.

The GNSS front end 304a includes appropriate logic, circuitry, and/or code for receiving GNSS satellite broadcast signals over the antenna 302 and converting them to GNSS baseband signals for further baseband signal processing in the processor 306.

The front end 304b includes suitable logic, circuitry, and/or code for transmitting and/or receiving RF signals by the antenna 302 over a telecommunications network, such as the wireless communication network 130. Front end 304b is capable of converting the received RF signal to a corresponding baseband signal for processor 306 to perform further baseband signal processing.

Processor 306 includes suitable logic, circuitry, and/or code for processing the received satellite signals and signals received from wireless communication system 130. The processor 306 is configured to enable it to extract navigation information from the received satellite models. The extracted navigation information is used to determine navigation information such as the positioning of the handset 110 that supports GNSS. Processor 306 is programmed to turn GNSS front end 304a on or off. For example, processor 306 periodically enters standby mode 220, in which GNSS front end 304a is turned on, information such as ephemeris from GNSS satellites 120a-120c is received. In the awake state 224, the processor 306 causes the GNSS enabled handset 110 to operate with minimal power consumption. For example, in the standby mode 220, the processor 306 periodically wakes up the GNSS front end 304a to receive GNSS signals, extract and store ephemeris, such as in received GNSS signals, without having to turn on the display screen or other in the GNSS enabled handset 110. A circuit that is not required to receive information. It is assumed that when navigation updates are required, for example, through user interface 310 or through various upper layer applications of wireless communication network 130, processor 306 can provide the latest ephemeris and store it in memory 308 for use.

Memory 308 includes suitable logic, circuitry, and/or code for storing information, such as executable instructions and materials used by processor 306. The executable instructions include an algorithm for extracting ephemeris from the received GNSS broadcast navigation signals and calculating a navigation scheme from the extracted ephemeris. The data includes GNSS navigation information, such as the latest ephemeris extracted. Memory 308 includes RAM, ROM, low latency nonvolatile memory such as flash memory and/or other suitable electronic data memory.

User interface 310 includes suitable logic, circuitry, and/or code for presenting navigation information. The navigation information may be presented in a graphical, audible manner in response to a user-entered navigation update request via, for example, a keyboard, a keypad, a thumbwheel, a mouse, a touch screen, an audio device, a trackball, and/or the like. Enter the method input.

In operation, antenna 302 coupled to GNSS enabled handset 110 receives a plurality of radio signals. The received plurality of radio signals can be transmitted to the GNSS front end 304a or the telecommunications front end 304b. When the GNSS enabled handset 110 is in the standby mode 220, the processor 306 can cause the GNSS enabled handset 110 to periodically switch between the sleep state 222 and the awake state 224 to conserve power. The awake state 224 allows the processor 306 to wake up the GNSS front end 304a to receive GNSS signals and obtain navigation information such as from GNSS satellites 120a-120c by using less power. In the awake state 224, the processor 306 can extract the complete ephemeris from the received GNSS signals and store the extracted ephemeris in the memory 308 accordingly. Without having to open the user interface 310, various operations such as obtaining the latest navigation information from satellite signals in the awake state 224 can be performed to save power. When a navigation update is required, the processor 306 uses the latest ephemeris stored in the memory 308 to generate a navigation scheme.

4 is a schematic flow diagram of maintaining a GNSS receiver in a hot start state, in accordance with an embodiment of the present invention. Referring to FIG. 4, an exemplary flow begins in step 402. It is assumed that the GNSS enabled handset 110 is turned on in the standby mode 220. In step 402, the GNSS enabled handset 110 selects a sleep interval and a wake interval. The sleep interval and wake-up interval are preset or dynamically adjusted based on one or more factors including QoS, satellite signal quality, battery life, and user input. In addition, the sleep timer and wake-up timer are reset. The sleep timer and wake-up timer are used to time control the complete sleep-wake cycle.

In step 404, it is determined if the GNSS enabled handset 110 is in the sleep state 222. Assuming that the GNSS enabled handset 110 is in the sleep state 222, then in step 406, it is determined if the sleep timer is overflowing and if there is sufficient remaining battery power. Assuming the timer overflows, then in step 408, the GNSS enabled handset 110 wakes up from the sleep state 224 and resets the wakeup timer. In step 410, the GNSS enabled handset 110 acquires the GNSS navigation signals, acquires/decodes the complete ephemeris from the acquired GNSS navigation signals, and stores the latest ephemeris into the memory 308. In step 412, it is determined whether the wake-up timer overflows; assuming the wake-up timer overflows, then in step 414, the GNSS-enabled handset 110 enters the sleep state 222 and resets the sleep timer, and then returns to step 406. In step 404, assume that the GNSS enabled handset 110 is not in the sleep state 222 and proceeds to the next step 410.

In step 406, assuming that the sleep timer has not overflowed and/or there is not enough remaining battery power, then continue in step 406. In step 412, assuming that the wake-up timer has not overflowed, then proceed to the next step 410. The GNSS enabled handset 110 can switch from the standby mode 220 (step 402) to the normal mode 210 for navigation updates. In step 416, it is determined whether a navigation update is requested. Assuming the GNSS enabled handset 110 requests navigation information, then in step 418, the GNSS enabled handset 110 enters the normal mode 210. In step 420, the processor 306 accesses the memory 308 to obtain the latest ephemeris to determine the requested navigation information. The GNSS enabled handset 110 then enters the sleep state 222. Depending on the implementation and/or QoS requirements, the GNSS enabled handset 110 can be configured to return from the normal mode 210 to the awake state 224 of the standby mode, or remain in the normal mode 210 after the navigation scheme is executed.

The present invention provides a method and system for maintaining a GNSS receiver in a hot-start state. In accordance with various embodiments of the present invention, a navigation satellite system receiver, such as handset GN that supports GNSS, operates in normal mode 210 and standby mode 220. In the standby mode 220, the GNSS enabled handset 110 is configured to periodically or non-periodically switch between the sleep state 222 and the awake state 224. For example, the GNSS enabled handset 110 in the standby mode 220 can transition from the sleep state 222 of the standby mode 220 to the awake state 224 of the standby mode 220. In the awake state 224, the processor 306 turns on the GNSS front end 304a to track satellite signals and obtain up-to-date navigation information, such as the latest ephemeris in the satellite signal. The latest navigation information obtained includes the latest ephemeris, stored in memory 308 and used to turn on GNSS enabled handset 110. The GNSS enabled device 110 uses the latest navigation information to generate a navigation scheme in the normal mode 210. After acquiring the latest ephemeris in the standby state 220, the GNSS enabled handset 110 transitions from the awake state 224 of the standby mode 220 to the sleep state 222 of the standby mode 220. The satellite signal can be a GPS signal, a GALILEO signal, and/or a GLONASS signal.

The GNSS enabled handset 110 can be implemented such that after various operations are initiated in the normal mode 210, the GNSS enabled handset 110 is configured to return to the sleep state 222 of the standby mode 220 or the awake state 224 of the standby mode 220, or to remain In normal mode 210. The sleep cycle of the sleep state 222 in the standby mode 220 and the wake-up cycle of the wake state 224 in the standby mode 220 are preset or dynamically adjusted. The sleep cycle in the standby mode 220 and the wake-up cycle in the standby mode 220 are determined based on exemplary factors including QoS, quality of satellite signals, and/or user input. The sleep period in the selected standby mode 220 is less than the period in which one or more satellites change the latest ephemeris. For the period required to collect the latest ephemeris, the wake-up period under the selected standby mode 220 should be sufficiently long.

Another embodiment of the present invention provides a machine and/or computer readable memory and/or medium having machine code and/or computer program stored thereon having at least one code segment executable by a machine and/or a computer such that the machine And/or the computer can implement the steps described herein to keep the GNSS receiver in a hot-start state.

In summary, the invention can be implemented in hardware, software, firmware or a combination thereof. The invention can be implemented in an integrated fashion in at least one computer system, or in a discrete manner by placing different components in a plurality of interconnected computer systems. Any computer system or other device suitable for performing the methods described herein is suitable. A typical combination of hardware, software and firmware is a dedicated computer system with a computer program that, when loaded and executed, controls the computer system to perform the methods described herein.

The present invention can also be embedded in a computer program product, including all features capable of ensuring the performance of the methods described herein. Once loaded in the computer system, the product is able to perform these methods. The computer program in the present invention may be in any form, any language, code or symbol, and has a set of instructions that enable the system to perform information processing functions directly or in one or two of the following ways: a) converting to another language, Code or symbol; b) reproduced in different ways.

The present invention has been described in terms of some embodiments, and those skilled in the art will be able to make various changes or equivalents to these features and embodiments without departing from the spirit and scope of the invention. In addition, these features and embodiments may be modified to adapt to the specific circumstances and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all the embodiments falling within the scope of the claims of the present invention fall within the scope of the present invention.

100‧‧‧GNSS satellite navigation system

110‧‧‧Support GNSS handsets

110a‧‧‧Supporting GNSS cellular phones

110b‧‧‧Smartphones that support GNSS (smartphone)

110c‧‧‧ Notebooks supporting GNSS (laptop)

120a-120c‧‧‧GNSS satellite

130‧‧‧Wireless communication network
210‧‧‧Normal mode

220‧‧‧ standby mode
222‧‧‧sleep state

224‧‧‧Awakening status
302‧‧‧Antenna

304a‧‧‧GNSS front end
304b‧‧‧Communication front end

306‧‧‧ Processor
308‧‧‧ memory

310‧‧‧User interface

1 is a schematic diagram of an exemplary GNSS satellite navigation system that maintains a GNSS receiver in a warm-start state, in accordance with an embodiment of the present invention;

2 is a state diagram of an exemplary GNSS receiver operation for maintaining a GNSS receiver in a warm start state, in accordance with an embodiment of the present invention;

3 is a schematic diagram of a preferred apparatus for supporting GNSS, the apparatus including a GNSS receiver for maintaining a hot start state, in accordance with an embodiment of the present invention;

4 is a schematic flow diagram of maintaining a GNSS receiver in a hot start state, in accordance with an embodiment of the present invention.

210‧‧‧Normal mode

220‧‧‧ standby mode

222‧‧‧sleep state

224‧‧‧Awakening status

Claims (10)

A satellite communication method, comprising:
When the navigation satellite system receiver is in a sleep state in the standby mode, transitioning from the sleep state to the awake state in the standby mode to obtain the latest ephemeris; and when the navigation satellite system receiver subsequently proceeds from the standby mode When converting to the normal operation mode, the navigation history information is determined using the acquired latest ephemeris. The satellite communication method of claim 1, wherein the method further comprises, after acquiring the latest ephemeris, transitioning from the awake state to the sleep state in the standby mode. The satellite communication method of claim 1, wherein the latest ephemeris is obtained from a GPS signal, a GLONASS signal, and/or a Galileo signal. The satellite communication method of claim 1, wherein the method further comprises storing the acquired latest ephemeris in the navigation satellite system receiver. The satellite communication method of claim 1, wherein the method further comprises returning from the normal operation mode to the sleep state in the standby mode. The satellite communication method of claim 1, wherein the method further comprises returning from the normal operation mode to the awake state in the standby mode. The satellite communication method of claim 1, wherein the method further comprises maintaining the normal operation mode after transitioning from the standby mode to the normal operation mode. A satellite communication system, comprising:
One or more circuits for a navigation satellite system receiver, wherein the one or more circuits are used to place the sleep state in a standby mode when the navigation satellite system receiver is in a standby state in a standby mode Converting to an awake state to obtain the latest ephemeris; and the one or more circuits for using the acquired ephemeris when the navigation satellite system receiver subsequently transitions from the standby mode to the normal mode of operation Determine navigation information. The satellite communication system of claim 8, wherein the one or more circuits are configured to convert the awake state back to the said standby mode after acquiring the latest ephemeris Sleep state. The satellite communication system of claim 8, wherein the latest ephemeris is obtained from a GPS signal, a GLONASS signal, and/or a Galileo signal.